6 gardenia ladies in 2 seasons!!! Same signs & symptoms.... 4 of them were dead in 2 months at max. But saved 2???

Start in one month after getting it from local stores/nurseries(April, May & June), signs of Mg & Fe deficiencies starting in the lower leaves... progressing to yellowing.crispy Green leaves & thirsty plant that will die no matter what.

What was interesting ? Not all the branches started to show the symptoms, one or 2 then the rest will follow.

No over/underwattering, fertilizing once as recommended for acid loving plants, no direct sun on the black plastic pots, 8 hours sun light exposure for the plant, one inch of water per week (divided in 3 doses).

After 1st 2 plants were dead, I decided to examine the roots: all brown , no hairy roots, very small root system was there .

Ok it was root rot... BUT WHY?Can't tell.

Next season....Time to get seduced by gardenia again....

I bought New 4 plants from different stores(originated from different nurseries)(just in case there was a root rot contamination or bad potting mix )....

Same signs & symptoms ....

Got me mad , start searching & hoping for any help about what is causing the root rot ,but nothing.

Time for fungicide ?in your dreams...

Nothing broad spectrum, nothing is available at local stores or just online & very expensive .

Decide to do it old school, drench the pot, remove as much as soil,clean the roots ,3% H2O2 with 4 parts water,minimize the green growth size, repot in new (clean!!) Mix.

Did that for 2 plants(died after one week)

Next day, time for the other 2

The drenching bowel was not clean, so no drench this time just turned the pots upside down to pull the plant root ball/ or what is left there....Boom : different things running white insect of small size & many larvae at different stages of development in both potting soils around the poor roots but still many white roots & few are showing classic signs of root rot in one plant, while the other plant's roots were in bad shape.

May be those things just started the infestation in the lats 2 pots,

I didn't pay attention to the soil in 2nd & 3rd plants , because of water drench inside the bowel & everything was dark brown (water& soil mix).May be those little things just acted like Elvis ...left the building after finishing what was there,roots.

Now ,time to get diagnosis for these 2 things, after searching , comparing photos& body features, signs & symptoms ,did a lot of reading : Root aphids+ fungus gnats.( search the web to find details about morphology, life cycle & control)

Both are attacking the hairy roots,leading to impaired root ability to absorb water & micronutrients ,thus the signs & symptoms of deficiencies & dehydration. At the same time any one of them is capable of doing such damage,while doing so ,it wounds the roots...wounds will be easy target for ehat ever soil-born fungus to attack & finish entire root system in few weeks.

What was recommended

1. change the potting mix (never mirac.grow), perlite &coco coir.

2 .Use sand in the bottom of the pot at least one inch) & on top 2 inches to cover the potting mix : sand is preventive measure, fungus gnats & Sand may be doing the same against root aphids.

So prevent it or deal with the consequences

3. You can use different ways to control the infestation, but the radical & nuclear thing was the chemical pesticide : imidacloprid that can be used as soil drench only for roses or plants in pots like gardenia BUT NEVER FOR EDIBLE PLANTS OR FRUITS.

I found one product by bayer , advanced complete insect killer for soil & turf.

Did the soil drench for 3 times each 72 hours apart(especially for root aphid life cycle) just to make sure this nuclear weapon is doing its job.

Move the one with extensive root damage to shade

Now,after 2 weeks, my 2 plants start to recover.

The one with less severe damage , is doing great & develops many new branches , green leaves& buds.

By the way it had few leaves with same signs, I left it there to assess the prognosis,so far so good.nofurther danage, no signs in other leaves.

The other one with extensive root damage ,is recovering, still has few green leaves& showing new growth.

Next step I will start posting the photos of my plants before the problem,during & after treatment.

I read many posts here in garden web , many other websites for more than 3 months but could not find any cause for root rot ... just overwatering which was not making any sense to me because I am not overwatering.

Same sings & symptoms in tons of posts .... nothing helped .

That was my experience & I am not recommending anything to anyone.

Do what ever you like to save your plants,

Happy gardening to you all.

Greetings,

San Antonio, Texas.